Nine environment groups and the Forest Product Association of Canada announced the agreement in Toronto, the Canadian Broadcasting Corp. reported Tuesday.
Companies agreed to the logging moratorium on the 71.6 million acres in exchange for a cessation of boycotts on Canadian paper and wood products that environmentalists had been pushing.
The agreement was the "best and last chance" at preserving a large tract for the woodland caribou, said Richard Brooks of Greenpeace.
The northern boreal forest in Canada covers 300 million hectares from western Canada to Newfoundland.
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